1. Field of the Invention
The present invention relates to a temperature control apparatus, and more particularly to a temperature control apparatus for holding a temperature of an IC chip to be tested by a handler at a predetermined temperature during the test.
2. Description of the Related Art
An IC chip has been used for the control of a consumer electric apparatus regardless of indoor and outdoor uses. A temperature condition for use of an IC chip extends over a wide range of −55° C. to +150° C. for example. An IC chip is checked for stable operation under such a temperature condition in the course of production and shipment. Therefore, a handler and a tester are used for testing an IC chip. For example, in a room temperature test, a socket is placed on a tester head at a room temperature, and an IC chip is placed on the socket. This test is performed by placing a room-temperature IC chip on a socket, and holding the IC chip to the socket by a pusher of a handler. However, the socket and pusher are influenced by the heat generated in the tester head and handler, and often heated to a temperature higher than a room temperature. Thus, the test is performed in a temperature condition higher than a room temperature. In a high-temperature test, IC chips are held at a predetermined high temperature by using a high-temperature bath provided in a handler, and a required number of IC chips is taken out, for example, one by one, and set on a socket. In this case, also, a socket is not set to a high temperature, and an IC chip is cooled by a socket immediately after being placed on the socket. As a result, an IC chip is tested at a temperature lower than a desired temperature.
Because of the above reason, an IC chip cannot be tested in a desired temperature condition. An IC chip not tested in a correct temperature condition is shipped, incorporated in an apparatus, and used. As a result, the quality of IC chip test is lowered, and the reliability of handler and tester is also lowered.
It is considerable to control a temperature in a tester head and handler to eliminate the influence to the temperature of an IC chip placed on a socket. However, it is necessary to modify largely a tester head or handler for this purpose. The modification cost is high, and increases the cost of IC chip test.